In medical operations, it is often not possible to grip and/or hold vessels, organs, tissue or other medical objects in a direct manual manner. This applies especially for micro-invasive operations. In these cases, gripping tools are used. Such tools constitute forceps-type instruments in a wider sense. For various applications, in particular tissues of different mechanical properties and different sensitivity, a broad range of different medical gripping tools is available to make possible a gripping or holding that is simultaneously secure and protective or atraumatic.
Newer developments aim at using synthetic for medical gripping tools. In particular in injection-molding methods, gripping tools can be produced in synthetic rapidly and in great number at reasonable cost. The greater elasticity of synthetic, especially in comparison with metals often used conventionally, makes possible to some extent a fundamentally different design. For example, solid-state joints can be provided.
In patents DE 10 2007 026 721 A1 and DE 10 2010 009 259.2, shape-adapting medical gripping tools are described that are based on the fin-ray effect. The aforementioned patent DE 10 2007 026 721 A1 also discloses a gripping layer that is coated with micro- or nano-particles, which are not specified in further detail. Patent DE 10 2007 050 018 A1 discloses a medical gripping tool with spring elements in fluid chambers or for the support of gripping surfaces. Patent DE 698 32 497 T2 describes a medical gripping tool with a gripping layer that is coated with metallic granules that are not joined together.
For some applications, however, medical gripping tools made of synthetic have insufficient mechanical solidity. For example, medical gripping tools of synthetic, when required to transmit torque onto the medical object that is being held, show an undesired reshaping, in particular a torsion that cannot be reduced or eliminated except at considerable construction cost.